Designed with the groundbreaking 'Sure Tread' deep-cleated outsole, the Stream II continues to lead the way in the premium wellington category. Its adjustable rear calf strap ensures a sleek and confident side profile. Waterproof rubber upper, 3.5mm insulated Neoprene lining, adjustable rear calf fitting, internal structured heel support, rubber kicker, rubber 'Sure-Trend' deep cleated sole, padded, removable insole. Unisex sizing. As the first boot built around the 'Sure Tread' deep cleated outsole, Stream II remains a trailblazer in the premium wellington category. The adjustable rear calf strap offers a clean and assured side profile. Upper: Rubber Lining & Sock: Neoprene Sole: Rubber.